Alternatively, you can choose Amazon suggested words by clicking on Add suggested keywords.

Select a keyword or keywords from list of keywords provided based on your book title.
Keywords on the ADDED KEYWORDS screen can be changed at will by pressing the Remove or Remove all buttons as applicable.

Customise your ad by typing or pasting ad keywords in the Custom Text box. (Only about 147/148 characters with no spaces, or ~128 characters including spaces). So, choose and plan your words very carefully).

Review your ad to check exactly how it will look like under Sponsored or Sponsored Products.

Set up your payment which is usually providing a credit or debit card for your ad campaign billing.

Simply select a card from the list provided.

Optionally, you may opt for another Payment Method by adding a new card that is not in your credit and debit card list.

At the moment, it’s just a blank screen with headings, but it gives an overview what it will look like once it’s populated with ad campaign metrics; number of clicks et al.

Hover mouse over the question mark next to each heading to reveal its definition. For instance,
Impressions; Impressions: An impression is generated every time your ad is displayed i.e number of displays or views.
Clicks; Clicks: A click is generated when a user clicks or taps your ad.
aCPC; Average Cost Per Click: Your total campaign spend divided by the total number of clicks the campaign generated.
And so on and so forth.

After a while, you will receive an email from Amazon Marketing Services.
If your ad was approved, the message will say something along the lines, ‘Your “————- xx/xx/2018 xx:xx” Ad campaign is approved‘ in the subject and ‘… Your ad “————- xx/xx/2018 xx:xx” has been approved…’ in the message body. Plus some more info and instruction of what to do next.

If, however, your ad was rejected, the email will read something like, “————- xx/xx/2018 xx:xx ad campaign was not approved” coupled with a hint or two of possible reasons for rejection (read carefully, including between the lines).
For instance, in my case, the ‘possible reasons’ were given as;
‘– The ad copy contains improper spacing between the words, incorrect punctuation or repetitive punctuation marks (for example, “!!!”)‘

And the typo mistake with my ad was a single comma at the end of the text – instead of a full stop (sorry, old eyes and punctuation marks being next to each other on keyboard).

Hence, it pays to study the statement in order to decipher the actual problem.

Once your ad campaign is approved, its Status will change from Pending review to Running with a green dot next to it.

Now, you can monitor and edit your ad; change the CPC bid plus Average daily budget & Duration via Campaign Settings, as well as, Pause or even Terminate (not recommended).